Are these Nassarius Snails?? (Pics included)

[woody189]

Hi. I recently purchased 15 Nassarius snails for $10 from a LFS.
I thought this was cheap so I bought them, but i'm not sure if they are in fact nassarius.
After doing some research, I realized that LFS's often sell Ilyanassa obsoleta or mud snails and label them as nassarius.
My snails have been in my tank for 3 days and not once have I seen them burrow under the sand. (ALL previous nassarius I've had always burrow. but all my old nass's are the beige/grey color, these are black, I have no experience w/ these.)
Also, when I pick them up, these snails retreat into their shell, my old nassarius' never go into their shell.
These are some pics, I can't get a clear shot, but here they are.
Do you think I should take them out, or are they OK?

 

[bigarn]

Can't tell what they are .... but they're not Nassarius IMO.

 

[renogaw]

they could be whelks also... the only nass. snails i buy are tonga ones for this reason alone.

 

[woody189]

Also, the new snails don't drag their bodies across the glass like the old ones do. And their bodies aren't nearly as long.
But the new ones have almost the same features...1 long siphon tube, and 2 little attachments.
And the new snails graze my LR, which is something I don't think my old nass's ever do.

 

[marcb]

Originally Posted by renogaw
http:///forum/post/2948985
they could be whelks also... the only nass. snails i buy are tonga ones for this reason alone.
I love my super tongan/fancy nassarius. They were spawing in my old tank like crazy. I brought over about 50 or so 1/4' baby ones, but the adults have yet to spawn in the new tank.

 

[woody189]

Is there any way to differentiate one snail from the other?
Are the characteristics I described useless?
I read that nass. snails eat only dead matter, and never touch algae. Is there any way for me to test this?
being as though I saw it on my LR, is that an indication that it was eating algae off my rock, therefore meaning it's not a nass??

 

[marcb]

I can't tell you for sure that those arent nassarius. However, I do have both of the more commonly available nassarius, and those arent them.
Occasionally something called black nassarius is available. From what I remember is that these werent true nassaruis, and might be harmful. However, that is from memory, and I could be mistaken.
All the nassarius I have are an almost creamy-beige color, none are dark like those you have. Look up whelks, see if they match your snails. If so, I would recommend removing them. also check Ilyanassa spp., from what I can tell, these may be ok.

 

[stanlalee]

they definately arent the more common vibex (small) or tonga (large). could be the east coast mud snails often sold as nassarius

 

[spanko]

Onyx Nassarius Snail Ilyanassa spp.
Curator's Note
Onyx Nassarius snails are very good at keeping sand beds completely clean of algae as well as other organics. Sometimes too good in fact. They may occasionally strip a sand bed of enough nutrients that there will be none left to support copepod or amphipod populations. If you keep dragonets, such as Green Mandarins, that rely on healthy populations of copepods and amphipods.
http://www.***************.com/images/products/Invertebrates/large/Onyx_Nassarius_Snail_ps.jpg

 

[dustyboy316]

I think you just nailed it.

 

[gmann1139]

Carolina mud snails.
You kind of get what you pay for with them. Not great at CU, but they make excellent food for hermit crabs.

 

[woody189]

Thanks for all the responses.
So should I just leave them in the tank? I don't really have anything to worry about unless they start attacking my other snails, correct? In which case I would remove them all

 

[woody189]

What I did was I grabbed all the "real" and all the "questionable" nass i could and threw them into a little cup (the one in the picture). i added some tank water, and threw them in my overflow box so it doesn't get cold.
I'll check on them in the morning to see if they did any damage to my "real" nass's. If they're okay, I guess I should be fine. i figure if they're gonna fight, it'll be in a confined spac elike that.
I have 8 black ones, and 3 Tongas in there.
From what i saw so far, the tongas were crawling all over the black ones. No hostitlity from the black ones yet

 

[woody189]

everyone seemed fine so I threw them all back in the tank. If I see any problems I'll remove them all.
Does that sound good? Or should I remove them just to be safe?

 

[stanlalee]

I had the mud snails (bought as nassarius from my LFS). they were never a problem but I always read bad things about them.